以树脂包覆石墨和电解铜粉为原料,采用粉末冶金加压烧结工艺制备树脂包覆石墨/铜复合材料,对材料的密度、孔隙率、电导率、硬度、抗弯强度、剪切强度和摩擦性能进行检测,结合扫描电镜研究树脂包覆石墨的含量对铜基复合材料显微组织和性能的影响。结果表明：随树脂包覆石墨含量增加,铜基体的连续性降低,石墨在复合材料中的分布由离散向局部偏聚转变。高含量的石墨阻碍了铜颗粒间的烧结致密,且石墨作为铜基体的“缺陷”,在影响铜基体烧结连续性的同时,降低了材料的密度、电导率、硬度、抗弯强度和剪切强度。作为润滑相,石墨有效地改善了材料的摩擦磨损性能。当树脂包覆石墨的添加量达到16%(质量分数)时,材料的摩擦因数最低(0.23),摩擦因数曲线较平稳,摩擦表面最光滑,复合材料具有最佳的摩擦磨损性能。
Resin-coated graphite/copper composites were prepared by powder metallurgy pressure sintering process using resin-coated graphite and electrolytic copper powders as raw materials, the density, porosity, conductivity, hardness, bending strength, shear strength, and friction property of the composites were measured, the effects of resin-coated graphite content on the microstructure and properties of copper matrix composites were studied by scanning electron microscope. The results show that the continuity of copper matrix gradually decreases, and the distribution of graphite is gradually changed from discrete to aggregate with the increase of resin-coated graphite content. The high content of graphite hinders the sintering densification of copper particles, and as a “defect”, graphite inhibits the sintering continuity of copper matrix, meanwhile the density, conductivity, hardness, bending strength, and shear strength of the composites are decreased. As a lubricating phase, the graphite can effectively improve the friction and wear property. When the addition of resin-coated graphite reaches 16% (mass fraction), the friction coefficient of the composites is the lowest (0.23), the friction coefficient curve is relatively stable, the friction surface is the smoothest, and the friction and wear property is the best.
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